Media operation - Overwrite media.
Compression Type: None
Encryption Type: None
DirectCopy to tape: Disabled
WARNING: The option 'Verify after backup completes' was not selected.
Performing a verify operation to make sure that media can be read after the backup has completed is recommended.

Backup started on 05-12-2012 at 21:34:03.
Duplicate completed on 05-12-2012 at 21:34:11.

Duplicate Set Summary

Backed up 0 files in 0 directories.
V-79-8192-4881 - The count of Files and Directories processed is not available for this operation. The File and Directory count might be displayed as zero.
Processed 218864121 bytes in 8 seconds.
Throughput rate: 1565 MB/min

Backup started on 05-12-2012 at 21:34:11.
Duplicate completed on 05-12-2012 at 21:36:38.

Duplicate Set Summary

Backed up 0 files in 0 directories.
V-79-8192-4881 - The count of Files and Directories processed is not available for this operation. The File and Directory count might be displayed as zero.
Processed 6.898.527.698 bytes in 2 minutes and 27 seconds.
Throughput rate: 2685 MB/min

Guess what i createa new backup storage destination inside the NAS so the path to it is \\srvnas01\backup\B2DEX and at the jobs i simply change the storage destination to this new storage wich is the same NAS but another folder olny to this exchange backups and now the jobs with duplication right way is working fine.

What can corrupt the backup history, i'm having this many times, i'm not liking it at all.

The server is always working normally, only get errors at BE nothing more.